Air duct blocking device for obstructing airflow through portions of an air duct system

ABSTRACT

The present invention discloses an air duct blocking device for obstructing airflow through portions of an air duct system. The blocking device may include a support plate having an interior side and an exterior side and an adjustable fastener configured on the exterior side. The air duct blocking device may include a flexible connector having a hook at one end that is capable of attaching to a register boot. The flexible connector passes through the support plate and the adjustable fastener, and the adjustable fastener is capable of securing the support plate in a fixed position relative to the flexible connector. The air duct blocking device may include a substantially planar gasket configured on the interior side of the support plate that is capable of blocking airflow through the register boot when the gasket is held against the register boot by the adjustable fastener secured to the flexible connector.

This application claims the benefit of and is a continuation-in-part of Non-Provisional Application No. 12/757,397 entitled“Air Vent Cover For Use In Testing Air Leakage Of An Air Duct System” and filed on Apr. 9, 2010, which is incorporated herein by reference in its entirety.

This application claims the benefit of Provisional Application No. 61/447,014 entitled “Installation And Removal Tool For Use With An Air Vent Cover For Sealing An Air Vent” and filed on Feb. 26, 2011, which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present invention relates to the field of air duct blocking devices for obstructing airflow through portions of an air duct system.

BACKGROUND ART

As the trend to conserve energy continues, more individuals are demanding and more governmental entities are mandating that houses and commercial facilities undergo periodic energy audits. An energy audit is a service where a building structure's energy efficiency is evaluated by a person using professional equipment as blower door and infra-red cameras), with the aim to suggest the best ways to improve energy efficiency in heating and cooling the structure.

An energy audit involves recording various characteristics of the building envelope including the walls, ceilings, floors, doors, windows, and skylights. For each of these components the area and resistance to heat flow (R-value) is measured or estimated. The leakage rate or infiltration of air through the building envelope is of concern and is strongly affected by window construction and quality of door seals such as weather stripping. The goal of an audit is to quantify the buildings overall thermal performance. The audit may also assess the efficiency, physical condition, and programming of mechanical systems such as the heating, ventilation, air conditioning (HVAC) equipment, and thermostat.

Leaks in an air duct system often account for a large percentage of energy being wasted in a typical home. In a residence, the percentage of air that escapes out of an air duct system due to leaks, on average, is approximately twenty-five percent (25%). Given that in some areas of the country, sixty percent (60%) to seventy percent (70%) of the cost of a households monthly utilities bill is due to the operation of the HVAC system, air leakage in an air duct system may represent a significant waste of both monetary and energy resources.

Measuring the leakage in an air duct system is generally the most time consuming portion of a home energy audit. In fact, as much as fifty percent (50%) of the time required to perform a home energy audit is consumed in testing air leakage of an air duct system. The majority of that time is spent sealing off the various air vents so that the air duct system can be pressurized or depressurized to measure the air leaks.

Current methods of sealing off the air vents involve the use of a special adhesive tape that adheres to the face of an air vent. There are, however, certain drawbacks to the use of this adhesive tape. Applying and removing the adhesive tape to all of the air vents takes a significant amount of time because the adhesive tape is cumbersome and awkward to use. Commonly, the tape sticks to itself and those pieces have to be thrown away unused. The tape is generally stored in bulky spools that are heavy and difficult to maneuver. When the tape is removed from the spools, it can generate an extremely loud noise that may wake up members of a home that are asleep during the day, such as, for example a baby or elderly person taking a nap, or be disruptive to ongoing business concerns.

Another drawback is that the tape does not provide the best seal possible for the air duct system. Even after the tape is applied to the air vent, air may still enter and leave the air duct system beneath the face of the air vent that touches the wall or ceilings surface because the tape only blocks the openings of the air vent on the face of the air vent. The tape does not block openings between the air vent and surface on which the air vent is installed. An additional drawback occurs when the tape is removed. Because the tape uses a strong adhesive, damage often occurs to the wall, ceiling, or air vent when the tape is removed.

Many audits of a building's HVAC system occur while the building is still under construction. For example, prior to the sheet rock being installed in a building, technicians will test an HVAC system for leaks and energy efficiency to allow for easy repair or adjustments prior the installation of surfaces that may hinder such repair or adjustment efforts. During subsequent construction, however, debris, dust, and dirt have the potential to enter into an HVAC system through the air vent boots and other openings in an HVAC system. Currently, construction workers attempt to prevent such debris from entering the HVAC system by taping cardboard to the HVAC openings or stuffing material into the openings to block the debris from entering. None of the current solutions serve to provide an effective seal, however, to protect the HVAC system during the final stages of construction.

SUMMARY OF INVENTION

The present invention discloses an air duct blocking device for obstructing airflow through portions of an air duct system. An air duct blocking device according to embodiments of the present invention may include a support plate having an interior side and an exterior side and an adjustable fastener configured on the exterior side of the support plate. Such an air duct blocking device according to embodiments of the present invention may include a flexible connector having a hook at one end. The hook is capable of attaching to a register boot in the air duct system, and the flexible connector passes through the support plate and the adjustable fastener. The adjustable fastener is capable of securing the support plate in a fixed position relative to the flexible connector. Such an air duct blocking device according to embodiments of the present invention may include a substantially planar gasket configured on the interior side of the support plate. The gasket is capable of blocking airflow through the register boot when the gasket is held adjacent to the register boot by the adjustable fastener being secured to the flexible connector.

Rather than utilizing a gasket, another air duct blocking device according to embodiments of the present invention may include a blocking plug configured on the interior side of the support plate. The blocking plug is capable of obstructing airflow through the register boot when the blocking plug is held against a collar inside the register boot by the adjustable fastener being secured to the flexible connector.

Still further, an air duct blocking device according to embodiments of the present invention may include a substantially planar cap having an adjustable fastener configured on an exterior side of the cap. The cap is capable of blocking airflow through a register boot of an air duct system when the cap is secured to the register boot. Such embodiments of an air duct blocking device may also include a flexible connector having a hook at one end. The hook is capable of attaching to the collar of the register boot in the air duct system. The flexible connector passes through the cap and the adjustable fastener, and the adjustable fastener is capable of securing the cap in a fixed position relative to the flexible connector.

BRIEF DESCRIPTION OF DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an implementation of apparatus and methods consistent with the present invention and, together with the detailed description, serve to explain advantages and principles consistent with the invention. In the drawings,

FIG. 1 sets forth a drawing illustrating a perspective view of an exemplary air duct blocking device for obstructing airflow through portions of an air duct system according to embodiments of the present invention during the installation of the air duct blocking device over a register boot.

FIG. 2 sets forth a drawing illustrating a perspective view of the exemplary air duct blocking device of FIG. 1 after the air duct blocking device is installed.

FIG. 3 sets forth a drawing illustrating a perspective view of an exemplary air duct blocking device for obstructing airflow through portions of an air duct system according to embodiments of the present invention during the installation of the air duct blocking device over an air vent register.

FIG. 4 sets forth a drawing illustrating a perspective view of the exemplary air duct blocking device of FIG. 3 after the air duct blocking device is installed.

FIG. 5 sets forth a drawing illustrating an orthogonal view of an exemplary air duct blocking device for obstructing airflow through portions of an air duct system according to embodiments of the present invention when installed on a straight register boot.

FIG. 6 sets forth a drawing illustrating an orthogonal view of an exemplary air duct blocking device for obstructing airflow through portions of an air duct system according to embodiments of the present invention when installed on an L-shaped register boot.

FIG. 7A sets forth a drawing illustrating a perspective view of a further exemplary air duct blocking device for obstructing airflow through portions of an air duct system according to embodiments of the present invention with tapered edges.

FIG. 7B sets forth a drawing illustrating an orthogonal view of the exemplary air duct blocking device in FIG. 7A.

FIG. 8 sets forth a drawing illustrating an orthogonal view of another exemplary air duct blocking device for obstructing airflow through portions of an air duct system according to embodiments of the present invention.

DESCRIPTION OF EMBODIMENTS

Exemplary embodiments of air duct blocking devices for obstructing airflow through portions of an air duct system are described herein with reference to the accompanying drawings, beginning with FIG. 1. FIG. 1 sets forth a drawing illustrating a perspective view of an exemplary air duct blocking device (100) for obstructing airflow through portions of an air duct system according to embodiments of the present invention during the installation of the air duct blocking device (100) over a register boot (114). Air duct systems are used in heating, ventilation, and air conditioning (HVAC) to deliver, circulate, or remove air using supply, return, or exhaust airflows. Air duct systems, therefore, are one method of ensuring acceptable indoor air quality as well as thermal comfort.

Though air duct systems vary from one installation to another, many air duct system share a common set of components. Air duct systems generally include an air handler unit that may be composed of a blower or fan, heating or cooling elements, filters, humidifier, mixing chamber, heat recovery device, controls, and vibration isolators. In addition, air duct systems typically include a network of plenums, ducts, and boots that direct airflow between the air handler unit and various air vents registers used to supply air to or return air from the spaces served by the air duct system. Readers will note that much of the air vent system is omitted from FIG. 1 and the remaining FIGS. 2-8 for clarity.

In FIG. 1, the air duct system includes a register boot (114). A register boot is a device that provides a physical interface between an air duct and an air vent register. The register boot (114) of FIG. 1 includes a collar (112) to which an air duct connects by sliding over the collar (112) and typically being secured by strap. An air vent register is an opening, typically forming a grill, in an air duct system that serves to supply air to or return air from a space served by the air duct system. Those of skill in the art often may collectively refer to an “air vent register” and “register boot” as an air diffuser, an air grate, or a terminal unit.

In the example of FIG. 1, an air duct blocking device (100) is placed over the register boot (114) to create a seal for inhibiting air flow through the register boot (114), and consequently a portion of the HVAC system, while testing air leakage of the air duct system. The air may attempt to flow through the register boot (114) due to either pressurization or depressurization of the air duct system during the leak testing process. Systems used to pressurize or depressurize an air duct system are known to those of skill in the art and may include, for example, the Minneapolis Duct Blaster® or the Retrotec Duct Testing Blower System.

The air duct blocking device (100) of FIG. 1 includes a support plate (102). The support place (102) of FIG. 1 provides a surface to which the other components of the air duct blocking device (100) may be connected. The support plate (102) of FIG. 1 has an interior side (104) and an exterior side (106). In the example of FIG. 1, the interior side (104) is the side of the support plate (102) that faces toward the register boot (114) when installed, and the exterior side of the support plate (102) that faces away from the register boot (114). The support plate (102) may be formed out of a variety of materials, including but not limited to, metal, carbon-composite, polyurethane, plastic, harden rubber, or any other material as will occur to those of skill in the art.

In the example of FIG. 1, the air duct blocking device (100) includes an adjustable fastener (108) configured on the exterior side (106) of the support plate (102). In FIG. 1, the adjustable fastener (108) is capable of adjusting the amount of a flexible connector that extends through the support plate (102) by pressing the pushbutton (126) on the adjustable fastener (108) and sliding a flexible connector through the adjustable fastener (108) to increase or decrease the amount of a flexible connector extending through the support plate (102). By increasing the length of a flexible connector extending through the support plate (102), enough slack is provided in the flexible connector of FIG. 1 to permit fast, easy attachment of the flexible connector to the collar (124) of the register boot (114). Then, decreasing the length of a flexible connector extending through the support plate allows the body of the air duct blocking device (100) to be secured against the register boot (114) thereby obstructing airflow through the register boot (114). Conversely, the body of the air duct blocking device may be easily removed by increasing the length of the flexible connector extending through the support plate (102) to provide enough slack in the flexible connector of FIG. 1 to permit fast, easy detachment of the flexible connector from the collar (124) of the register boot (114).

The exemplary the air duct blocking device (100) of FIG. 1 also includes a flexible connector (110). The flexible connector (110) of FIG. 1 removeably attaches to the collar (124) of the register boot (114) using a hook (112) and extends through the support plate (102) and adjustable fastener (108). Readers will note that the use of a hook is for example only, not for limitation. Other components for removeably attaching the flexible connector to the collar of a register boot as will occur to those of skill in the art may also be used such as a clip or other fastener. Preferably, though not required, the flexible connector is configured for easy attachment and detachment using one hand while holding the cover portion with the other hand.

The flexible nature of the flexible connector (110) facilitates quick and easy attachment to and detachment from the register boot (114). A flexible connector provides certain advantages over a rigid connector, which is often used in long-term or permanently installed covers. Rigid connectors, such as those fashioned from a system of nuts and bolts, are cumbersome and more time-consuming to attach and detach because the air vent cover must be precisely placed in the proper orientation for a rigid connector to connect with the air vent. For example, when using a rigid connector made up of a bolt through the air vent cover, typically the air vent cover has to be lined up with the connection point on the air vent. After lining up the air vent cover, however, the air vent cover often blocks or covers the connection point for the rigid connector on the air vent, thereby enhancing the difficulty associated with making the connection between the rigid connector and the collar of the register boot. When using a flexible connector, however, there is no requirement that the air duct blocking device be aligned with the air vent register boot when attaching the connector the collar of the register boot because the flexible connector can bend or twist in the manner needed to quickly and easily connect to the air vent.

In fact, in the example of FIG. 1, the flexible connector (110) is configured to be rigid in a first orientation and bendable along a second orientation. In this manner, the flexible connector provides a technician with the benefits of flexibility but also provides the stability that comes from a rigid structure. A flexible connector that provides rigidity along one plane but flexibility along another plan may be composed of many discrete components connected together that hinge along one plan but not in any other planes. Structures similar to those that may be useful in such a flexible connector may include such structures as those used to form bicycle chains, albeit those in a flexible connector would be much smaller. To prevent the flexible connector from bending unless adequate force exerting along the flexible plane, certain dents may be placed near hinges points so that the weight of the flexible connector itself would not be enough to cause it to bend along the flexible plane. Rather, some additional force such as hitting the flexible connector against the interior wall of the register boot may be required to cause the flexible connector to bend along the flexible plane. Readers will note that other structures that provide the ability of the flexible to be rigid in a first orientation and bendable along a second orientation as will occur to those of ordinary skill in the art may also be useful in embodiments of the present invention.

The exemplary the air duct blocking device (100) of FIG. 1 includes a substantially planar gasket (116) configured on the interior side (104) of the support plate (102). In FIG. 1, the gasket (116) is capable of blocking airflow through the register boot (114) when the gasket (116) is held adjacent to the register boot (114) by the adjustable fastener (108) being secured to the flexible connector (110).

A gasket is a mechanical seal that fills the space between two mating surfaces. Gaskets allow “less-than-perfect” mating surfaces to seal by filling in irregularities of the mating surfaces. For example, use of the gasket (116) helps create a seal around the edges of the register boot (114) because the gasket (116) engulfs portions of the register boot (114) when the gasket (116) is pressed against the register boot (114). Also, for uses when the air duct blocking device (100) is used to a seal a register boot with the air vent register installed, the gasket of may help the air duct blocking device seal against rough surface such as an interior ceiling or wall with a popcorn texture or other rough texture or even the louvers of the register itself. In this manner, a gasket blocks the flow of air between the inside and outside of the register boot while under compression. The gasket may be formed from a variety of materials as will occur to those of skill in the art, including, for example, foam, rubber, nylon, or plastic. When formed from material such as foam, readers will note that there are two types of foam that could be used to create a gasket according to embodiments of the present invention-open-cell foam and closed-cell foam.

In open-cell foam, the cell walls, or surfaces of the bubbles, are broken and air fills all of the spaces in the material. In this manner, open-cell foam creates a permeable barrier that may allow air to flow through it when uncompressed. When compressed, however, the open-cell foam may provide enough of a barrier to serve as a seal. The open-cell nature makes the foam soft or weak, as if it were made of broken balloons or soft toy rubber balls. The insulation value of this foam is related to the insulation value of the calm air inside the matrix of broken cells.

In closed-cell foam, most of the cells or bubbles in the foam are not broken; they resemble inflated balloons or soccer balls, piled together in a compact configuration. This makes the closed-cell foam strong or rigid because the bubbles are strong enough to withstand high-pressure. Although closed-cell foam is rigid, it has varying degrees of hardness, depending on its density. Because the cell walls of closed-cell foam are not generally broken, closed-cell foam provides greater resistance to air leakage than that of open-celled foam.

In the example of FIG. 1, the flexible connector (110) has an outer surface that is textured to increase friction between flexible connector (110) and the adjustable fastener (108). This increased friction helps prevent slippage by the flexible connector (110) through the adjustable fastener (108) over time, thereby reducing the likelihood that the seal between the air duct blocking device (100) and the register boot (114) is broken. In some embodiments, the flexible connector (110) and the adjustable fastener (108) may be configured to operate together as a ratchet system. The outer surface of the flexible connector (110) may include ratchet teeth, and the adjustable fastener (108) may incorporate a ratchet claw. Unless the pushbutton (126) is depressed, the ratchet system formed by the flexible connector (110) and the adjustable fastener (108) would only permit the flexible connector (110) to move in one direction-through the support plate (102) toward the exterior side (106). When the pushbutton (126) is depressed, the adjustable fastener (108) would allow the flexible connector (110) to move freely back and forth.

For further illustration, FIG. 2 sets forth a drawing illustrating a perspective view of the exemplary air duct blocking device (100) of FIG. 1 after the air duct blocking device is installed over a register boot (114).

FIG. 3 sets forth a drawing illustrating a perspective view of an exemplary air duct blocking device for obstructing airflow through portions of an air duct system according to embodiments of the present invention during the installation of the air duct blocking device over an air vent register. The air duct blocking device (100) of FIG. 3 is similar to the air duct blocking device (100) of FIG. 1. That is, the air duct blocking device (100) of FIG. 3 includes a support plate (102) having an interior side (104) and an exterior side (106) and an adjustable fastener (108) configured on the exterior side (106) of the support plate (102).

The air duct blocking device (100) of FIG. 3 also includes a flexible connector (110) having a hook (112) at one end. The hook (112) in FIG. 3 is capable of attaching to a register boot (114) in the air duct system. The flexible connector (110) of FIG. 3 passes through the support plate (102) and the adjustable fastener (108). The adjustable fastener (108) of FIG. 3 is capable of securing the support plate (102) in a fixed position relative to the flexible connector (110).

The air duct blocking device (100) of FIG. 3 includes a substantially planar gasket (116) configured on the interior side (104) of the support plate (102). The gasket (116) of FIG. 3 is capable of blocking airflow through the register boot (114) when the gasket (116) is held adjacent to the register boot (114) by the adjustable fastener (108) being secured to the flexible connector (110).

In the example of FIG. 3, an air vent register (120) is attached to the register boot (114) of the air duct system. The air vent register (120) of FIG. 3 is mounted adjacent to a surface surrounding the air vent register (120). In the example of FIG. 3, the surface is the interior wall of a room served by the air duct system. In embodiments of the present invention, however, the surface surrounding an air vent register may be any surface of a room or structure, including a wall, floor, ceiling, or any other surface as will occur to those of skill in the art. The air vent register provides a face for the air vent and may serve a decorative or functional purpose. For example, the grill may include an ornamental design or provide a mechanism for directing airflow.

The air vent register (120) of FIG. 3 has one or more louvers. A louver is a baffle used to direct or control the flow of air through an air vent. A louver may extend beyond the face of the air vent register, as in the example of FIG. 3, or may be inset into the face of the register. Still further, some louvers may be placed inside the air vent register. A louver may be fixed in place or allowed to move through a range of positions. In fact, many air vent registers are designed with both fixed and moveable louvers. Whether fixed or moveable, a louver may be configured at a slanted angle or perpendicular to the face of the register. In the example of FIG. 3, the louvers are fixed in place at slanted angles and are formed as integral components with the register (120).

In FIG. 3, the gasket (116) is capable of blocking airflow through the register boot (114) when the gasket (116) is held against the air vent register (120). The gasket (116) is held against the air vent register (120) in FIG. 3 by sliding the flexible connector (110) through the louvers and hooking it to the collar (not shown) of the register boot (not shown) to which the register (120) attaches. After hooking the flexible connector (110) to the register boot (not shown), the body of the air duct blocking device (100) may be slid along the flexible connector (110) until the gasket (116) is pressed against the register (120) and engulfs any protruding portions of the register (120). At that point, the adjustable fastener (108) may be secured to the flexible connector (110), thereby holding the air duct blocking device (100) in place against the register to seal off airflow.

Turning to FIG. 4, FIG. 4 sets forth a drawing illustrating a perspective view of the exemplary air duct blocking device (100) of FIG. 3 after the air duct blocking device is installed against the air vent register (120 in FIG. 3; not shown in FIG. 4).

The register boots depicted in FIGS. 1-4 are configured such that the register boot collar extends away from the side of the register boot where the air vent register attaches. Readers will note, however, that register boots may come in variety of shapes. Accordingly, FIGS. 5 and 6 depict an exemplary air duct blocking device according to embodiments of the present invention installed on two different styles of register boots.

FIG. 5 sets forth a drawing illustrating an orthogonal view of the exemplary air duct blocking device (100) of FIG. 1 for obstructing airflow through portions of an air duct system according to embodiments of the present invention when installed on a straight register boot (114). The register boot (114) is “straight” in the sense that the collar (124) extends away from the portion (122) of the register boot (114) against which the body of the air duct blocking device (100) is secured. That is, the axis along which the collar (124) extends is perpendicular to the plane along which the air duct blocking device (100) connects to the register boot (114). When secured against that portion (122) of the register boot (114), the gasket (116) engulfs that portion (122) of the register boot (114) to create a seal that obstructs airflow through the portion of the air duct system connected to that register boot (114).

Turning to FIG. 6, FIG. 6 sets forth a drawing illustrating an orthogonal view of an exemplary air duct blocking device for obstructing airflow through portions of an air duct system according to embodiments of the present invention when installed on an L-shaped register boot (140). The register boot (140) is “L-shaped” in the sense that the collar (142) extends along an axis parallel to the plane along which the air duct blocking device (100) connects to the register boot (140). When secured against that portion (144) of the register (140), the gasket (116) engulfs that portion (144) of the register (140) to create a seal that obstructs airflow through the portion of the air duct system connected to that register boot (140). By engulfing the register boot (140), additional friction exists between the gasket (116) and the register boot (140) that prevents the body of the air duct blocking device (100) from sliding toward the point at which the hook (112) is attached to the collar (142).

FIGS. 7A and 7B set forth drawings illustrating different views of another exemplary air duct blocking device (300) for obstructing airflow through portions of an air duct system according to embodiments of the present invention with tapered edges. In particular, FIG. 7A sets forth a drawing illustrating a perspective view of this exemplary air duct blocking device (300).

The exemplary air duct blocking device (300) of FIG. 7A includes a substantially planar foam cap (302). The foam cap (302) of FIG. 7A has an adjustable fastener (308) configured on an exterior side of the foam cap (302). The foam cap (302) capable of blocking airflow through a register boot when the foam cap (302) is secured to a register boot of an air duct system. In the example of FIG. 7A, the foam cap (302) has an edge region (328) that is tapered away from the adjustable fastener (308). The tampered edge allows the foam cap (302) to be thinner at the outer edges, which allows those outer edges to be more flexible. The advantage to having more flexibility at the outer edges of the foam cap (302) is that multiple foam caps may be stacked next to one another in a slightly overlapping fashion to seal off air vents that are larger than any one air duct blocking device itself.

The exemplary air duct blocking device (300) of FIG. 7A also includes a flexible connector (310) having a hook (shown as 312 in FIG. 7A) at one end. The hook (shown as 312 in FIG. 7A) is capable of attaching to the collar of the register boot in the air duct system. The flexible connector (310) passes through the foam cap (302) and the adjustable fastener (308), which operates to secure the foam cap (302) in a fixed position relative to the flexible connector (310).

Turning to FIG. 8, FIG. 8 sets forth a drawing illustrating an orthogonal view of another exemplary air duct blocking device (200) for obstructing airflow through portions of an air duct system according to embodiments of the present invention. In the example of FIG. 8, the air duct blocking device (200) includes a support plate (202) having an interior side (204) and an exterior side (206). The air duct blocking device (200) of FIG. 8 also includes an adjustable fastener (208) configured on the exterior side (206) of the support plate (202).

Similar to the other exemplary air duct blocking devices, the air duct blocking device (200) of FIG. 8 also includes a flexible connector (210) having a hook (212) at one end. The hook (212) of FIG. 8 is capable of attaching to a register boot (214). The flexible connector (210) of FIG. 8 passes through the support plate (202) and the adjustable fastener (208). The adjustable fastener (208) is capable of securing the support plate (202) in a fixed position relative to the flexible connector (210).

While the other exemplary air duct blocking devices described utilized a gasket, the air duct blocking device (200) of FIG. 8 includes a blocking plug (216). The blocking plug (216) of FIG. 8 is configured on the interior side (204) of the support plate (202) and is capable of obstructing airflow through the register boot (214) when the blocking plug (216) is held against a collar (224) inside the register boot (214). The blocking plug (216) is held against the collar (224) inside the register boot (214) by the adjustable fastener (208) being secured to the flexible connector (210) using friction, a ratchet type system, or any other mechanism as will occur to those of skill in the art.

While certain exemplary embodiments have been described in details and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative of and not devised without departing from the basic scope thereof, which is determined by the claims that follow. 

1. An air duct blocking device for obstructing airflow through portions of an air duct system, the air duct blocking device comprising: a support plate having an interior side and an exterior side; an adjustable fastener configured on the exterior side of the support plate; a flexible connector having a hook at one end, the hook capable of attaching to a register boot in the air duct system, the flexible connector passing through the support plate and the adjustable fastener, the adjustable fastener capable of securing the support plate in a fixed position relative to the flexible connector; and a substantially planar gasket configured on the interior side of the support plate, the gasket capable of blocking airflow through the register boot when the gasket is held adjacent to the register boot by the adjustable fastener being secured to the flexible connector.
 2. The air duct blocking device of claim 1 wherein the gasket is configured to engulf portions of the register boot pressed against the gasket.
 3. The air duct blocking device of claim 1 wherein: the air duct system comprises an air vent register attached to the register boot; and the gasket is capable of blocking airflow through the register boot when the gasket is held against the air vent register by the adjustable fastener being secured to the flexible connector.
 4. The air duct blocking device of claim 3 wherein the gasket is configured to engulf portions of the air vent register that protrude into the gasket.
 5. The air duct blocking device of claim 1 wherein the hook of the flexible connector attaches to a collar of the register boot.
 6. The air duct blocking device of claim 1 wherein the adjustable fastener comprise a pushbutton configured to allow the flexible connector to pass freely through the adjustable fastener when the pushbutton is depressed and to hold the flexible connector in a fix position relative to the adjustable fastener when the pushbutton is released.
 7. The air duct blocking device of claim 1 wherein the gasket comprises an outer edge region that is tapered away from the support plate.
 8. The air duct blocking device of claim 1 wherein the flexible connector comprises an outer surface that is textured to increase friction between flexible connector and the adjustable fastener.
 9. The air duct blocking device of claim 1 wherein the flexible connector and the adjustable fastener are configured to operate together as a ratchet.
 10. The air duct blocking device of claim 1 wherein the perimeter of the gasket is larger than the perimeter of the support plate.
 11. The air duct blocking device of claim 1 wherein the flexible connector is configured to be rigid in a first orientation and bendable along a second orientation.
 12. The air duct blocking device of claim 1 wherein the support plate along a first dimension is at least as large as an opening along a corresponding dimension of the register boot.
 13. An air duct blocking device for obstructing airflow through portions of an air duct system, the air duct blocking device comprising: a support plate having an interior side and an exterior side; an adjustable fastener configured on the exterior side of the support plate; a flexible connector having a hook at one end, the hook capable of attaching to a register boot, the flexible connector passing through the support plate and the adjustable fastener, the adjustable fastener capable of securing the support plate in a fixed position relative to the flexible connector; and a blocking plug configured on the interior side of the support plate, the blocking plug capable of obstructing airflow through the register boot when the blocking plug is held against a collar of the register boot by the adjustable fastener being secured to the flexible connector.
 14. The air duct blocking device of claim 13 wherein the flexible connector comprises an elastic cord.
 15. The air duct blocking device of claim 13 wherein the flexible connector comprises a hook for attaching the flexible connector to a collar of the register boot.
 16. The air duct blocking device of claim 13 wherein the flexible connector is configured to be rigid in a first orientation and bendable along a second orientation.
 17. An air duct blocking device for obstructing airflow through portions of an air duct system, the air duct blocking device comprising: a substantially planar cap, the cap having an adjustable fastener configured on an exterior side of the cap, the cap capable of blocking airflow through a register boot of an air duct system when the cap is secured to the register boot; and a flexible connector having a hook at one end, the hook capable of attaching to the collar of the register boot in the air duct system, the flexible connector passing through the cap and the adjustable fastener, the adjustable fastener capable of securing the cap in a fixed position relative to the flexible connector.
 18. The air duct blocking device of claim 17 wherein the cap is configured from spongy material.
 19. The air duct blocking device of claim 17 wherein the cap is foam. 